Valve and actuating mechanism for fluid motors



Nov. 1, 1949.

J. E. ELKINGTON VALVE AND ACTUATING MECHANISM FOR FLUID MOTORS FiledJune 18, 1945 3 Sheets-Sheet 1 Noml, 1949. E K N 2,486,707

VALVE AND ACTUATING MECHANISM FOR FLUID MOTORS INVENTOR. JAMES, E .EKma-roN Nov, 1,. 1949. J. E. ELKENGTON ,4

VALVE AND AC'I'UATING MECHANISM FOR FLUID MOTORS Filed June 18, 1945 3Shets-Sheet 3 J: a 53 r -11- 7 1 4Q 47 INVENTOR. JAMES F. .t\ \N6TONPatented Nov. 1 1949 UNITED STATES PATENT OFFICE VALVE A'ND ACTUATINGMECHA- NlSM FOR FLUID MOTORS James E. Elking'ton, SanFrancisco, Calif.

Application June .18, 1945, Serial No. 600,089

.3 Claims. .1

This invention relates to a 'dishwashing machine and particularly to ahydraulic actuator or prime mover for reciprocating a dish tray movingrack in and through the washing zone of said machine; said actuatorbeing made to reciprocate by hydraulic pressure in alternating cycles.

An object of the invention is to provide a hydraulic actuator whichincludes a plunger made to reciprocate by applying hydraulic pressure inalternating cycles to opposite faces of the plunger thru theinstrumentality of a valve timer synchronized to operate with theplunger and to control its operation.

In the accompanying three sheets of drawings:

Fig. 1 is a side elevation of a dish washing machine constructed inaccordance with my .invention, showing my hydraulic reciprocater-operatively applied thereto.

Fig. 2 is an end elevation of Fig.

Fig. 3 is a plan view of the rack (for reciprocating the dish trays)having my reciprocator applied thereto.

Fig. 4 is a cross-section taken thru one side of the dish washingmachine showing the relationship of the slide rack, trays and trayguides.

Fig. 5 is a longitudinal section of a hydraulic actuator or prime moverconstructed in accordance with my invention, illustrated in itsapplication to a slide rack on a dishwashing machine, the plunger of theactuator being secured to the rack while the actuator mechanism is'fixed on One end of the washing machine struc-' ture.

Fig. 6 is a front view of the valve chamber i with the operativemechanism removed.

Fig. 7 is an enlarged cross-section taken thru the valve chamber on theline of Fig. *5.

Fig. 8 is a view of the rear face of the actuator valve.

Fig. 9 is a cross-section taken through Fig.8 0n the line 99.

Fig. 10 is a rview of the front face of the actuator valve.

Fig. 11 is .a front elevation of the valve chamber showing the operativemechanism mounted therein.

Fig. 12 is a side elevation of the yoke for actuating the valve.

In detail the construction illustrated in .the drawings comprises inFigs. 1 and 2 a .dish washing machine which in its entirety isdesignated bythe numeral 38'. This dish washing machine includes, inaddition to the necessary structural frame Work, a water tank 3|, .fiuidspray pipes 32,.a fluid pump 33 :and a motor '34, a reciprocating rack35 mounted over the tank 31 and between the spray pipes 32 for :movingtrays 36 of dishes and the like thru the washing zone :on the parallelguides 31 which extend longitudinally thru the machine.

'The dirty dishes or other articles to be washed are placed by hand intrays 36 and the loaded traysare placed on the entrant endlof guides 31.The guides 3! are 'tormed'of spaced complementary angle bars and beneath:said guides the reciprocating rack 85, see Fig. 3, is slidably mounted.The rack 35 :is formed of parallel bars 33 connected by transversemembers 6. The bars 38 rest and slide'upon brackets 39mounted onopposite sides of the machine as shown in Fi .4.

The inside face of each of the bars 38 is provided,

at spaced intervals between the ends thereof, with counterweightedgpawls i!) pivotally mounted thereon. The upper end 411 .of each pawl 40is adapted toengage ribs .or serrations (not shown) on the under side ofthe dish trays 36 for the purpose of intermittently advancing said .dishtrays thru the washing process from the entrant end .of the tray guides.31 to the discharge end thereof. The rack 3:5 is reciprocated on a-horizontal plane in the manner to be hereinafter described. Whenthe;r,acl.35 sis reciprocated forwardly toward the discharge end of thewashing machine the upper end 44 of each ;pawl engages the dish trays 36and advances them, with an intermittent movement, along the tray guides31. .On the return stroke of the rack 35 the pivoted pawls -40 disengagefrom the dish trays but automatically swing upwardly into contact withthe vdish trays upon .the start of the forward stroke :of the rack 35.

The type of rack 35 .hereinabove described for advancing the dish "traysthru the wash zone is only one of many types of similar racks whichparallel endless belts could be actuated intermittently by my primemover for moving the dish trays thru the machine. It is to be understoodthat while I have developed the prime mover particularly for its use .ona .dish washing machine, that the reciprocative impulses developed by itcould be applied .to ,or utilizedon many-other machines of a type andkind needing a reciprocative movement in some phase of their operations.

Spaced nested cylinders 2 .and 3 are mounted on the base I and areclosed at the end-opposite to the base I by a cap 1. The cap 1 issecured to the base I' by rods, welding or otherwise.

The cap I is drilled centrally with the axis of the cylinders 2 and 3 toprovide a bore in which a shaft 8 is slidably confined. The outer end ofthe shaft 8 is fixed to the cross member 6 of the rack, while the innerend of the shaft 8, within the inner cylinder 3, has a plunger or piston9 mounted thereon.

The end of the shaft 8 where it is secured to plunger 9 is drilledaxially at II]. This open bore I8 is closed by a hollow plug H. A stemI2 is slidably confined in the plug II and the end of the stem withinthe bore has an annular shoulder l3 there around to limit the movementof the stem in one direction. The opposite end of the stem I2 extendsthrough a hole in the base I into the reservoir 4 where it has attachedthereto a yoke M which is related mechanically to the valve structure tobe hereinafter described. The valve structure consists of the valveplate I1, see Figs. 8, 9 and 10. The valve I1 is pivotally mounted atits bottom end on a pin l8 fixed in the chamber 4. The valve l1 has aflat face l9 which is operatively mounted in relation to three ports2!], 2| and 23, on one wall of the chamber 4. The port 28 communicatesdirectly with the inner cylinder 3, Figs. and 6, while the port 2|communicates with the space between the inner and outer cylinders 2 and3 and through the port 22 with the interior of the inner cylinder at apoint near the outer end thereof, see Fig. 5. Midway between the ports28 and 21 is the port 23 which latter port is an exhaust or relief port,through which spent fluid pressure from cylinder 3 flows to a collectiontank 43 on the base of the machine 30. In order to communicate theexhaust port 23, alternately, with the ports 20 and 2|, the flat face E9of the valve I1 is recessed at 24, the length of said groove beingsufiicient to connect the ports" 20 and 23 or 2! and 23, dependingupon'the position of the valve I 1.

F.uid under pressure is developed by a rotary pump 44 connected to themotor 34. The fluid pressure is delivered thru a line 25 to the valvechamber 4, while the spent fluid is returned from said chamber through aline 45 to the tank 43. A pipe 26 supplies fluid from the tank 43 to thepump 4 The valve is mechanically swung back and forth by the yoke l4.The yoke l4 has a slot 46 therein. A pin 41 has one end slidablyconfined in the slot 46 while the head 48 of the pin is confined in anoval slot 49 in the valve l1. A pair of radially disposed pins 50 and 5|are arranged on diametrically opposite sides of the center pin 41, eachof pins 50 and 5| having an eyelet 52 confined on the center pin 41. Theouter end of each of the pins 50 and 5| is confined in a recess 53 inthe inner wall of the chamber 4. An expansion spring 54 is mountedaround each of the pins 50 and 5|. The yoke I4 is provided with ears 55and 56' on one face thereof, said ears lying on opposite sides of theeyelets 52 on the center pin 41.

In the operation of the device hydraulic pressure is delivered to thechamber 4 from the pump 44. The valve i1 being positioned as shown inFigs. 5 and 11, fluid pressure passes from the chamber 4, thru port 2|]and into the inboard end of the cylinder 3, causing the plunger to moveoutwardly in the direction of the arrows, thereby forcing the inert oilon the outboard side of the plunger to be moved into and thru the port22 and discharge port 23 to the collection sump 43.

When the plunger reaches the extreme limit of its outboard movement, thestem 12 exerts a pull on the yoke l4, the ears of which engage theeyelets 52 on the center pin 41 forcing the pins 50 and 5| from theoff-center position shown in Figs. 5 and 11 to an opposite off-centerposition. The movement of the pins 50 and 51 from one offcenter positionto the other, causes the springs 54 to be momentarily compressed up tothe time said pins 50 and 5| reach an aligned dead center position.Immediately after passing the deadcenter position, the pent up pressureof the compressed springs is released causing the pins 50 and 5| to snaprapidly out and in, so doing, causing the valve H to move rapidly fromone operating position to the other. The spaced compression springs and56 located in the lower periphery of the chamber 4 are designed todeaden the impact of the valve l1 when snapping from one position to theother. The change of position of the valve closes the port 20 and opensthe port 2 I. Immediately fluid pressure starts feeding out thru theport 2|, thru the space between cylinders 2 and 3, and thru the port 22into the outboard end of the inner cylinder 2 to work against theoutboard face of the plunger 9 causing it to move inwardly. Oil on theinboard side of the plunger is discharged out thru the port 20 anddischarge port 23. When the plunger 9 reaches the inboard end of itsstroke the yoke on the stem l2 exerts a pull on the center pin 41 andcauses it to snap the valve over from one position to the other, thusimmediately reversing the direction of flow of the fluid pressure andthe plunger 9. The alternate reversal of directional movement of theplunger continues automatically as long as there is fluid pressuredirected into the apparatus.

The valve I1 is only one form of device for synchronizing the movementof the plunger and timing the delivery of fluid pressure to oppositefaces of the plunger and it is to be understood the inventioncontemplates that other types and kinds of valve timers might be used inplace of the specific form of device illustrated and described herein.

Having thus described this invention, what I claim and desire to secureby Letters Patent is: 1. Hydraulic apparatus comprising a cylinder; apiston in said cylinder; a source of liquid under pressure; conduitmeans extending between said cylinder and source; a valve interposed insaid conduit means to control the application of hydraulic pressure fromsaid source to opposite faces of the piston; said valve having anarcuate surface; pivot means for said valve eccentrically disposed withrespect to said surface; a link member interconnecting said piston andvalve to oscillate said valve about said pivot means in timed relationwith the piston stroke and thereby control the application of hydraulicpressure at intermittent intervals to opposite faces of the piston forreciprocating said piston; and a spring substantially radially disposedwith respect to said surface stressed by said valve in a terminalposition thereof serving to accelerate the movement of the valve at thecommencement of its oscillation.

2. Hydraulic apparatus comprising a cylinder; a piston in said cylinder;a source of liquid under pressure; conduit means extending between saidcylinder and source; a valve interposed in said conduit means to controlthe application of hydraulic pressure from said source to opposite facesof the piston; said valve having an arcuate surface; pivot means forsaid valve eccentrically disposed with respect to said surface; a linkmember interconnecting said piston and valve to oscillate said valveabout said pivot means in timed relation with the piston stroke andthereby control the application of hydraulic pressure at intermittentintervals to opposite faces of the piston for reciprocating said piston;an overcenter spring imparting a snap action to said valve in itsoscillating movements; and a spring substantially radially disposed withrespect to said surface stressed by said valve in a terminal positionthereof serving to accelerate the movement of the valve at thecommencement of its oscillation.

3. Hydraulic apparatus comprising a cylinder; a piston in said cylinder;a source of liquid under pressure; conduit means extending between saidcylinder and source; a valve interposed in said conduit means to controlthe application of hydraulic pressure from said source to opposite facesof the piston; said valve having an arcuate surface; pivot means forsaid valve eccentrically disposed with respect to said surface; a linkmember interconnecting said piston and valve to oscillate said valveabout said pivot means in timed relation with the piston stroke andthereby control the application of hydraulic pressure at intermittentintervals to opposite 6 faces of the piston for reciprocating saidpiston; and a pair of springs substantially radially disposed withrespect to said surface alternately stressed by said valve in theterminal positions thereof serving to accelerate the movement of thevalve at the commencement of each stroke of its oscillation.

JAMES E. ELKINGTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 196,958 Weir Nov. 6, 18771,766,988 Farr June 24, 1930 1,770,931 Lathrop Jul 22, 1930 1,993,154Elkington Mar. 5, 1935 2,103,001 Evans et a1 Dec. 21, 1937 2,235,544Wold Mar. 18, 1941 2,265,306 Orshansky Dec. 9, 1941 2,269,423 Barks etal Jan. 13, 1942 FOREIGN PATENTS Number Country Date 16,606/34 AustraliaJan. 4, 1935

